FLOWCHART


Flowchart is a graphical or pictorial Representation of algorithm or process.

A flowchart is a type of diagram that represents an algorithm or process, showing the steps as boxes of various kinds, and their order by connecting these with arrows.
This diagrammatic representation can give a step-by-step solution to a given problem.
Data is represented in these boxes, and arrows connecting them represent flow / direction of flow of data.
Flowcharts are used in analyzing, designing, documenting or managing a process or program in various fields.
A flowchart is a picture, which shows the sequence in which data are read, Computations are performed, decisions are made and results are obtained.
It makes use of the basic operations in programming.
All symbols are connected among themselves to indicate the flow of information and processing.

Symbols

A typical flowchart will have the following kinds of symbols:
Start and End (or) Terminals
Represented as ovals or rounded rectangles, usually containing the word "Start" or “Begin” and "End" or “Stop”.




Flow direction
Arrow coming from one symbol and ending at another symbol represents that control passes to the symbol the arrow points to.


Process (or) Action

Rectangle represents the processing operation. A process changes or moves data. An assignment is normally represented by this symbol.
 

Input/Output
 Represented as parallelogram. The parallelogram represents the Input/Output function i.e. making data available for processing (input) or recording of the processed information (output).
  

Condition or Decision making
Represented as Diamond or Rhombus. These typically contain a Yes/No question or True/False test. This symbol is unique in that it has two arrows coming out of it, usually from the bottom point and right point, one corresponding to Yes or True, and one corresponding to No or False. The arrows should always be labeled.
 



Connector
The circle represents a function in a flow line.
 
 Annotation
            A broken line and bracket represent the annotation function – the addition of descriptive comments or explanatory notes for clarification of some statements.
                                                                                                              


Flowchart Design Rules

1.  Must begin with START and end with STOP symbol.
2.  Standard process flow should be either from top to bottom or left to right.
3.  Instructions specified in the flowchart should be clear and concise.
4.  Arrows must be aligned properly so as to clearly describe the flow of program control.
5.  Use of excess connectors should be avoided as they make the flowchart complex.
6.  Process or Action symbol must have only one input arrow and one output arrow.
7.  Two arrows must never intersect or cross each other. if such need arises, use appropriate
     Bridge or Crossover symbols.
8. Condition symbol should have one input arrow and can have maximum of two output   
    Arrows.

Advantages
  1. Communication: Flowcharts are better way of communicating the logic of a system to all concerned.
  2. Effective analysis: With the help of flowchart, problem can be analysed in more effective way.
  3. Proper documentation: Program flowcharts serve as a good program documentation, which is needed for various purposes.
  4. Efficient Coding: The flowcharts act as a guide or blueprint during the systems analysis and program development phase.
  5. Proper Debugging: The flowchart helps in debugging process.
  6. Efficient Program Maintenance: The maintenance of operating program becomes easy with the help of flowchart. It helps the programmer to put efforts more efficiently on that part
Limitations
  1. Complex logic: Sometimes, the program logic is quite complicated. In that case, flowchart becomes complex and clumsy.
  2. Alterations and Modifications: If alterations are required the flowchart may require re-drawing completely.
  3. Reproduction: As the flowchart symbols cannot be typed, reproduction of flowchart becomes a problem.
  4. The essentials of what is done can easily be lost in the technical details of how it is done.



















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